How do I remove all HTML tags from a string without knowing which tags are in it?

Pitfalls in the regex method

While the regular expression does seem like a knight in shining armor, it isn’t always the perfect solution. If your HTML input has nested tags or attributes containing > within their values, this method could lead to unintended tag removals or missed opacities.

Alternative option: HTML parsing libraries

When the going gets tough, the tough get HTML parsing libraries! Libraries like the HTML Agility Pack (.NET) or jsoup (Java) provide more robust solutions that account for the complex structure of HTML. Here's an example of how to use HTML Agility Pack:

var htmlDoc = new HtmlAgilityPack.HtmlDocument();
htmlDoc.LoadHtml(htmlString);
var cleanText = htmlDoc.DocumentNode.InnerText; // Tada! Your fairy godmother at work!
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Clever handling of HTML entities

Don't get lost in the mysterious world of HTML entities. After waving goodbye to the tags, remember to replace entities like < and & with their actual characters. As if by magic, most parsing libraries handle entity conversion for you.

Zooming in on regular expressions

Regex can indeed be your friend if you get to know them better. Strengthen the regex pattern to face scenarios where tags span across multiple lines:

// How does it feel to level up, huh?
const cleanText = htmlString.replace(/<(?:.|\n)*?>/gm, ''); 
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This non-greedy (*?) regex now matches patterns across newlines (|\n), too, broadening its tactical armor.

The hidden icebergs of regex

As you navigate the sea of HTML manipulation with regex, be wary of hidden icebergs. Unforeseen regex limitations can sneakily remove more than needed or skip unexpected patterns.

Leveling up with StringBuilder and Regex

For those who want to take it up a notch, consider combining a StringBuilder (in powerhouse languages like .NET/C#,). This enables lightning-fast string manipulation while avoiding time-consuming string constructions.

Achieving surgical precision with HTML parsers

Libraries like the HTML Agility Pack yield Incision-level precision thanks to their nuanced methods like InnerText, which inherently respect the DOM hierarchy.

The aftermath: Validating the output

Once the dust settles, ensure your text is as clean as a whistle. Use services like the W3C Markup Validation Service to sanitise your textual output.

Closing words

Remember, practice makes perfect. If this answer helps, consider upvoting it. Because votes keep this coding wizard motivated. Happy coding!👩‍💻